If you want to enhance the appearance of your plain, drab-looking concrete fence posts by coating them with paint, consider a few things before you begin. First, unlike wood, concrete is poorly suited for paint adhesion, and tends to shed paint relatively soon after application. Prepare the posts to accept paint before you begin the application process. In addition, if you want your finish to remain durable in varying weather conditions, choose a paint that possesses good elasticity, allowing it to expand and contract as temperatures dip and soar.
Remove vegetation growing on or alongside each concrete fence post, using hedge trimmers. Clear grass from the bottoms of the posts, using an edger or a garden hoe.
Clean the concrete posts with a pressure washer. Ensure that all dust and dirt have been removed, or the primer and paint may not adhere properly. Wait for the posts to dry.
Coat the cleaned concrete with an acrylic latex primer, using a 7.5 to 10 cm (3 to 4 inch) latex paintbrush. Wait two hours for the posts to dry.
Wash the brush with plain tap water.
Coat the primed concrete with an acrylic latex paint just as you did the primer.
Work on a warm day free from rain and high winds.
Do not paint in temperatures below 7.22 degrees Celsius (45 degrees Fahrenheit), or the paint will not properly cure. Do not paint over dusty or dirty concrete fence posts, or the paint will not stick. Do not paint directly over bare concrete, or the finish will fail. Do not use a plain latex paint in place of an acrylic latex paint, or your finish will not last as long.